Between the two inaugurations of Barack Obama, expectation and reality have been turned on their head. When America's first black president took the oath of office on that frigid, unforgettable 20 January 2009 in Washington, the mood was of exhilaration – but amid the deepest economic slump in three-quarters of a century and two unfinished wars, the prospects by any rational measure were sobering. How different now. His first term yielded much, including a stimulus package that probably warded off a depression, and a giant step towards universal US health coverage. Yet today the mood is downbeat, the dreaded term "lame duck" is on every lip. But the pessimism is misplaced. In fact, this is a moment of rare and real opportunity to tackle America's problems, and the Obama second term – in contrast to that of his predecessor George W Bush – could be one to remember for all the right reasons.
The President has learnt a lot, not least how intractable are the partisan, interest group-driven ways of Washington. He will not repeat his first-term mistake of making only small use of the famous presidential bully-pulpit, in the misguided belief that politics is a business where common sense and a spirit of co-operation automatically prevail. Four years of unrelenting, unbending Republican hostility have disabused him of that notion.
The window of opportunity will not last more than 18 months, before the next midterm elections and then the 2016 campaign for the White House, take over American politics completely. But between now and mid-2014, Mr Obama is in a remarkably favourable position. For one thing, he has no more elections to fight, and thus less need to pander. A strengthening economy, and America's under-reported but vastly significant progress towards energy self-sufficiency add to his freedom of manoeuvre.
As for the Republicans, the truth is starting to sink in after their emphatic presidential defeat last November: you cannot seek to dictate national policy through a majority in a House of Representatives that is about as popular as the bubonic plague. It is worth remembering too that Americans as a whole did not want a Republican House. Democrats won the popular Congressional vote by some half a million nationally, but gerrymandering is a wonderful thing. In fact, it seems that the Republicans have already blinked in the most feared immediate confrontation, over a renewal of the US federal debt ceiling, without which the country might have defaulted. Their proposal, for a three-month extension is far from perfect. But it shows the party has realised that politics as kamikaze warfare is self-defeating.
Mr Obama should seize the opening, by advancing his own proposals to bring the deficit under control, including curbs on the growth of entitlement programmes which his own party will dislike. A "grand bargain" is possible. And if not now, when? Inaction will merely ensure the problem will be even worse, when a new president takes office in 2017.
He also has a decent chance to add immigration reform to his list of achievements. Many Republicans now appreciate that alienation of the Hispanic vote is a recipe for losing elections. Measures to tackle climate change are a more distant, but not wholly unattainable, goal. But Mr Obama must seize the moment. If his first term revealed a flaw, it was a passivity based on assuming his opponents would be susceptible to reason. But here too – if the urgency with which he is pressing for gun control is any indicator – that lesson has sunk home. And if so, he might deliver a second term that makes history.